Known in the art is a functional component mounting base that mounts a functional component, such as a pressure sensor, a temperature sensor, a battery or a power generating element, a wireless device, or a sensor module combining them, on the inner surface of a tire.
A tire fitted on a vehicle rolls, when the vehicle travels, on the ground with the lowest part of the periphery thereof in contact with the ground. Thus the non-contacting part of the tire moves in rotational motion while the ground-contacting part thereof moves in linear motion. Accordingly, there occur states of imbalance in centripetal forces as the tire rotates at the leading end, a boundary at which a non-contacting periphery of the tire keeps changing into a ground-contacting periphery, and at the trailing end, another boundary at which a ground-contacting periphery of the tire keeps changing into a non-contacting periphery. And inertia forces act on the functional component mounted on the inner surface of the tire through the functional component mounting base. These inertia forces increase with the revolution speed of the tire and can sometimes reach several dozen kgf. As a result, the functional component mounting base with a functional component mounted thereon may suffer damage, and the functional component may fall off the base.
Also, the inner surface of the tire in the non-contacting part maintains a certain curvature, but is horizontal in the ground-contacting part. As the tire rolls, therefore, there occur repetitive distortions in the direction of tire rotation. Furthermore, when the tire passes over a large bump, the inner surface of the tire may undergo an inverse R deformation, thus causing a large distortion in the direction of tire rotation. Hence, the functional component mounting base may get damaged with the functional component falling off the base.
Known as a remedial measure is a functional component mounting base that has a structure featuring improved high-speed durability. This functional component mounting base has a rubber bottom plate which is equipped with a functional component securing mechanism consisting of a frame body and an insertion piece having a predetermined rigidity (see Patent Document 1, for instance).